Effects of Novel 3-dimensional Antibiotic-containing Electrospun Scaffolds on Dentin Discoloration

Introduction: Although intracanal application of the triple antibiotic paste (TAP) may offer advantages (eg, disinfection), this practice has been associated with significant drawbacks, including tooth discoloration. In this study, the color change of dentin was monitored during treatment with distinct TAP pastes and novel tubular-shaped 3-dimensional electrospun scaffolds containing minocycline (MINO) or doxycycline (DOX). Methods: Two TAP pastes (TAP(MINO) [MINO, metronidazole, and ciprofloxacin] and TAP(DOX) [DOX, metronidazole, and ciprofloxacin]), 4 scaffold-based groups containing MINO or DOX at distinct concentrations, 1 antibiotic-free scaffold, and 1 untreated group (control) were investigated. Human canines were sectioned at the cementoenamel junction and tubular-shaped scaffolds or paste were placed into the root canals and sealed. Color measurements (CIEL*a*b* parameters) were performed at baseline and after 1, 3, 7, 14, 21, and 28 days. Color changes were expressed as Delta E* values. In addition, scanning electron microscopy and energy-dispersive X-ray spectroscopy were also performed on the specimens after treatment. Data were analyzed using repeated measures analysis of variance (alpha = 0.05). Results: All antibiotic-containing groups led to greater discoloration than the antibiotic-free groups. A severe discoloration occurred after 1 day. At the end of the experiment, antibiotic-treated samples exhibited crusts/agglomerates over the dentin surface, which totally or partially obliterated the dentinal tubules. The presence of MINO resulted in a greater color change than DOX. Conclusions: Scaffolds containing MINO or DOX produced similar color change to dentin when compared with their respective TAP systems, although DOX-related discoloration was less pronounced.